1) Skin improvement / Anti-aging

1. Shurrab K, et al. Low-level laser therapy for skin rejuvenation: systematic review and meta-analysis. J Cosmet Dermatol. 2024.

https://pubmed.ncbi.nlm.nih.gov/38817003/

• Population: Aggregated clinical studies on skin elasticity, wrinkles and melasma.
• Intervention: Various LLLT/LED protocols (red and near-infrared).
• Key findings:
  • Improved skin elasticity
  • Reduction of wrinkles
  • Considered a safe and useful adjunctive therapy
• Study type: Systematic review (2024).
• Strengths/Limitations: Recent meta-analysis; limitations due to varying dosages and outcomes.

2. Couturaud V, Le Fur M, Pelletier M, Granotier F. Reverse skin aging signs by red light photobiomodulation. 2023.

https://www.researchgate.net/publication/372014314_Reverse_skin_aging_signs_by_red_light_photobiomodulation

• Population: 20 healthy white women with combination to oily skin, age not specified.
• Intervention: LED mask (~630 ±10 nm, ~15.6 J/cm²), 2 sessions per week for 3 months (12 min per session).
• Key findings:
  • ~16.7% reduction in facial sagging
  • ~31.3% increase in dermal density
  • ~28.1% decrease in pore diameter
  • ~62.6% decrease in sebum production
  • Effects persisted for 14–28 days after discontinuation
• Study type: Clinical intervention study without control group.
• Strengths/Limitations: Small sample size, no placebo group.

3. Mota LR, et al. Photobiomodulation reduces periocular wrinkle volume by 30%: a randomized controlled trial (2023)

https://pubmed.ncbi.nlm.nih.gov/36780572/

• Population: 137 women aged 40–65 years with skin phototype II–IV.
• Intervention: 10 sessions in 4 weeks of red (660 nm) and amber (590 nm) light, split-face model.
• Key findings:
  • ~31.6% wrinkle reduction with red light
  • ~29.9% wrinkle reduction with amber light
  • No significant improvement in hydration or viscoelasticity
• Study type: Randomized, controlled split-face study.
• Strengths/limitations: Focused on the periocular area, short follow-up.

4. Jagdeo J, et al. Light-emitting diodes in dermatology: A systematic review. J Am Acad Dermatol. 2018.

https://pmc.ncbi.nlm.nih.gov/articles/PMC6099480/

• Population: Various clinical studies (photo-aging, acne, wound healing).
• Intervention: Red (630–660 nm) and NIR (830–880 nm) light in different protocols.
• Key findings:
  • Improved wrinkles
  • Increased skin elasticity
  • Collagen stimulation
  • Up to 26–36% wrinkle reduction in some studies
• Study type: Systematic review.
• Strengths/Limitations: Wide variation in dosages and devices.

5. Wunsch A & Matuschka K. A controlled trial… Photomed Laser Surg. 2014.

https://pmc.ncbi.nlm.nih.gov/articles/PMC3926176/

• Population: Adults who received full-face PPE.
• Intervention: Polychromatic red/NIR light for several weeks.
• Key findings:
  • Higher patient satisfaction
  • Reduction of fine lines
  • Increase in collagen density
• Study type: Controlled clinical trial.
• Strengths/Limitations: Device dependent; standardized dosages required.

6. Avci P, et al. Low-level laser therapy (LLLT) in skin. Lasers Surg Med. 2013.

https://pmc.ncbi.nlm.nih.gov/articles/PMC4126803/

• Population: Clinical and preclinical data.
• Intervention: Red light (600–700 nm) and NIR (760–1100 nm).
• Key findings:
  • Increase in ATP production
  • Stimulation of collagen synthesis
  • Increased fibroblast activity
• Study type: Narrative/systematic review.
• Strengths/Limitations: Strong mechanistic rationale.

2) Faster recovery, muscle recovery & sports performance

1. Luo WT, et al. Effects of Low-Level Laser Therapy on Muscular Performance and Recovery: Systematic Review & Meta-analysis. Front Physiol. 2021.

https://pmc.ncbi.nlm.nih.gov/articles/PMC9460079/

• Population: 24 clinical trials in athletes and active adults.
• Intervention: LLLT/PBM before or after training, wavelengths 630–904 nm.
• Key findings:
  • Improved muscle strength when applied before exercise
  • Reduced muscle damage (lower CK levels)
  • Reduced muscle pain
• Study type: Meta-analysis.
• Strengths/Limitations: Many studies; variation in dosage and timing.

2. Tomazoni SS, et al. Infrared Low-Level Laser Therapy applied before running test. Lasers Med Sci. 2019.

https://pmc.ncbi.nlm.nih.gov/articles/PMC6885272/

• Population: Healthy, active adults.
• Intervention: IR-LLLT (808–830 nm) applied before a progressive walking test.
• Key findings:
  • Better performance while running
  • Lower fatigue indicators compared to placebo
• Study type: Randomized clinical trial.
• Strengths/Limitations: Well-controlled; one session — no long-term data.

3. Rossato M, et al. Dose-response effect of photobiomodulation on exercise performance. Lasers Surg Med. 2020.

https://pubmed.ncbi.nlm.nih.gov/33232629/

• Population: 18 physically active men.
• Intervention: PBM on different energy doses applied to the quadriceps before exercise.
• Key findings:
  • Clear dose-response relationship
  • More repetitions possible before fatigue
  • Reduced muscle fatigue
• Study type: Randomized crossover study.
• Strengths/Limitations: Small sample size but excellent control.

4. Lanferdini FJ, et al. Effects of Photobiomodulation Therapy on Performance in Sports: Randomized Trials & Mechanisms. Sports Med. 2023.

https://pmc.ncbi.nlm.nih.gov/articles/PMC10594465/

• Population: Athletes and active adults.
• Intervention: PBM before or after exercise, usually 660–850 nm.
• Key findings:
  • Improved oxygen dynamics in muscles
  • Less muscle damage after exercise
  • Faster muscle recovery processes
• Study type: Systematic review.
• Strengths/Limitations: Comprehensive overview; need for uniform dosages.

5. Ailioaie LM & Ailioaie C. Photobiomodulation and sports: a narrative review with an RCT example. 2021.

https://pmc.ncbi.nlm.nih.gov/articles/PMC8706093/

• Population: Healthy men (RCT) + broader sports population in review.
• Intervention: PBM applied to biceps before resistance exercise.
• Key findings:
  • Lower fatigue during testing
  • Longer time to muscle failure
• Study type: RCT + narrative review.
• Strengths/Limitations: Focuses on one muscle group; broader research needed.

6. De Oliveira et al. Photobiomodulation preconditioning improves muscular performance: systematic review (2018).

https://pubmed.ncbi.nlm.nih.gov/29090398/

• Population: Randomized trials with athletes/healthy participants.
• Intervention: PBM applied before training or exercise.
• Key findings:
  • Consistent reduction of muscle fatigue
  • Improved performance in various sports tests
• Study type: Systematic review & meta-analysis.
• Strengths/Limitations: Strong support; variety in protocols.

3) More energy & less fatigue

1. Salehpour F., et al. Transcranial PBM improves brain energy metabolism via cytochrome-c oxidase activation (2023)

https://pmc.ncbi.nlm.nih.gov/articles/PMC10552827/

• Population: Overview of animal and human studies on brain energy and mitochondria.
• Intervention: Red/NIR brain PBM (usually 630–1064 nm).
• Key findings:
  • Increased activity of cytochrome c oxidase
  • Increased ATP production in the brain
  • Better cognitive energy availability
• Study type: Systematic review.
• Strengths/Limitations: Strong mechanistic evidence; clinical parameters vary.

2. Naeser MA., et al. Transcranial PBM for chronic brain dysfunction — improved fatigue & cognition (2022)

https://pmc.ncbi.nlm.nih.gov/articles/PMC9271305/

• Population: Patients with long-term cognitive complaints.
• Intervention: Red/NIR tPBM applied to the prefrontal cortex.
• Key findings:
  • Less mental fatigue
  • Improved attention and processing speed
  • Improved mood
• Study type: Clinical intervention study.
• Strengths/Limitations: Promising; no placebo control.

3. Vargas E., et al. PBM increases cerebral oxygenation & alertness (NIR 1064 nm) — randomized trial (2017)

https://pmc.ncbi.nlm.nih.gov/articles/PMC5445709/

• Population: Healthy adults.
• Intervention: 1064 nm NIR on forehead for 8 minutes.
• Key findings:
  • Increased oxygen supply to the brain
  • Higher alertness
  • Possible increase in mental energy
• Study type: Randomized controlled trial.
• Strengths/Limitations: Strong physiological measures; short intervention duration.

4. Henderson TA, et al. Neuroenergetic benefits of PBM — review (2022)

https://pubmed.ncbi.nlm.nih.gov/35149652/

• Population: Human and animal models focused on energy supply to neurons.
• Intervention: Various PBM wavelengths from 630–1064 nm.
• Key findings:
  • Increased ATP synthesis
  • Lower oxidative stress
  • Improved mitochondrial function
• Study type: Mechanistic review.
• Strengths/limitations: Strong biological basis; variation between studies.

5. Darlot F, et al. PBM reshapes energy metabolism in neurons — experimental & translational evidence (2022)

https://pubmed.ncbi.nlm.nih.gov/35413191/

• Population: Animal and cell studies supplemented with early clinical data.
• Intervention: PBM with red/NIR for mitochondrial stimulation.
• Key findings:
  • Improved ATP production
  • Better energy efficiency in neurons
  • Potential application for fatigue complaints
• Study type: Translational research review.
• Strengths/limitations: Promising; limited large-scale human data.

6. Hwang J, et al. PBM for mental fatigue — randomized sham-controlled trial (2016)

https://pubmed.ncbi.nlm.nih.gov/27285902/

• Population: Healthy adults with mental fatigue.
• Intervention: 825 nm tPBM targeted to frontal brain areas.
• Key findings:
  • Significant reduction in mental fatigue
  • Improved cognitive performance
• Study type: Double-blind, placebo-controlled study.
• Strengths/Limitations: Strong design; one session — long-term effect unknown.

4) Pain reduction (muscle & joint pain)

1. González-Muñoz A, et al. Efficacy of photobiomodulation therapy in the treatment of pain and inflammation: Systematic review (2023)

https://pmc.ncbi.nlm.nih.gov/articles/PMC10094541/

• Population: Clinical trials of acute and chronic musculoskeletal pain.
• Intervention: Local application of red and near-infrared PPE.
• Key findings:
  • Reduction of pain scores in multiple RCTs
  • Reduced inflammatory markers
  • Improved tissue repair
• Study type: Systematic review.
• Strengths/limitations: Good number of RCTs; variation in dosage and parameters.

2. Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation (2017)

https://pmc.ncbi.nlm.nih.gov/articles/PMC5523874/

• Population: Preclinical and clinical studies on inflammation and pain.
• Intervention: Red/NIR PBM on cells, animal models and human tissues.
• Key findings:
  • Decrease in pro-inflammatory cytokines
  • Increased M2 macrophages (convalescent type)
  • Reduced oxidative stress
• Study type: Mechanistic review.
• Strengths/Limitations: Strong biological basis; need for uniform clinical protocols.

3. Tomazoni SS, et al. IR LLLT before exercise reduces post-exercise soreness and markers (2019)

https://pmc.ncbi.nlm.nih.gov/articles/PMC6885272/

• Population: Healthy male athletes.
• Intervention: Infrared LLLT before intensive exercise.
• Key findings:
  • Significant reduction of muscle pain after exercise
  • Lower CK levels and oxidative stress
  • Better muscle recovery markers
• Study type: Randomized, placebo-controlled trial.
• Strengths/Limitations: Highly controlled; short-term and small group only.

4. Tsou YA, et al. Effects of PBMT for delayed-onset muscle soreness: systematic review & meta-analysis (2025)

https://pmc.ncbi.nlm.nih.gov/articles/PMC12286287/

• Population: Studies of muscle soreness (DOMS) in healthy adults.
• Intervention: PBM applied before or after exercise.
• Key findings:
  • Reduction of DOMS intensity at different time points
  • Better muscle function during recovery
• Study type: Systematic review and meta-analysis.
• Strengths/Limitations: Good number of trials; effectiveness depends on time of application.

5. Zecha FJ, et al. LLLT/PBM in oral mucositis & tissue injury (2016 review)

https://pmc.ncbi.nlm.nih.gov/articles/PMC4846477/

• Population: Cancer patients with oral mucositis due to chemo or radiation.
• Intervention: Local LLLT on oral mucosa.
• Key findings:
  • Significant pain reduction
  • Accelerated healing of oral lesions
  • Reduced severity of mucositis
• Study type: Systematic review with practice guidelines.
• Strengths/limitations: Very strong clinical evidence; specific medical context.

6. González-Muñoz A, et al. PBM as adjunctive therapy for chronic musculoskeletal pain (2023)

https://www.mdpi.com/2076-3417/15/8/4161

• Population: Patients with knee osteoarthritis, tendinopathy and low back pain.
• Intervention: PBM added to physiotherapy or standard care.
• Key findings:
  • Additional pain relief on top of regular therapy
  • Improved functionality
• Study type: Systematic review and trial summary.
• Strengths/limitations: Positive picture; need for larger RCTs.

5) Neurological benefits (focus, memory & cognition)

1. Naeser MA, et al. Improved cognitive function after transcranial LED treatments in chronic TBI (2011 / 2016)

https://pmc.ncbi.nlm.nih.gov/articles/PMC3104287

• Population: Persons with chronic traumatic brain injury (TBI) and cognitive impairment.
• Intervention: Repeated transcranial red/NIR LED sessions (633–870 nm).
• Key findings:
  • Improved attention
  • Improved memory
  • Improved executive functions
• Study Type: Pilot Clinical Reports.
• Strengths/Limitations: Consistent improvements; need for larger controlled RCTs.

2. Qu X, et al. Repeated transcranial photobiomodulation improves working memory in older adults (2022)

https://pmc.ncbi.nlm.nih.gov/articles/PMC9514540/

• Population: Healthy older adults.
• Intervention: Seven-day series of NIR tPBM sessions.
• Key findings:
  • Working memory improved immediately after the treatments
  • Effect lasted for several weeks
• Study type: Randomized controlled trial.
• Strengths/Limitations: Well-controlled; limited sample size.

3. de Oliveira BH, et al. tPBM increases cognitive function & BDNF in adults with MCI (2024)

https://pubmed.ncbi.nlm.nih.gov/39423445/

• Population: Adults with mild cognitive impairment (MCI).
• Intervention: tPBM sessions vs placebo/sham.
• Key findings:
  • Improved cognitive performance
  • Increase in circulating BDNF (neurotrophic factor) levels
• Study type: RCT.
• Strengths/Limitations: Strong design; need for long-term research.

4. Urquhart EL, et al. Transcranial PBM-induced changes in EEG and cognition (2020)

https://pmc.ncbi.nlm.nih.gov/articles/PMC7587286/

• Population: Healthy adults.
• Intervention: Single session NIR tPBM (830 nm).
• Key findings:
  • Increased delta and theta EEG activity (associated with relaxation and cognitive modulation)
  • Short-term cognitive improvements
• Study type: Controlled experimental study.
• Strengths/limitations: Strong neurophysiological data; small sample size.

5. Pan W, et al. Advances in photobiomodulation for cognitive impairment (2023 review)

https://pmc.ncbi.nlm.nih.gov/articles/PMC9945713/

• Population: Preclinical models and human studies in TBI, dementia, and cognitive decline.
• Intervention: Red/NIR tPBM.
• Key findings:
  • Improved cerebral blood flow
  • Mitochondrial support
  • Improvements in cognitive outcomes across multiple studies
• Study type: Review.
• Strengths/Limitations: Very comprehensive; clinical protocols vary widely.

6. Nizamutdinov D, et al. Transcranial Near-Infrared (tNIR) light in dementia: safety & cognitive effects (2021)

https://pmc.ncbi.nlm.nih.gov/articles/PMC8219492/

• Population: Patients with dementia.
• Intervention: Repeated tNIR treatments at home.
• Key findings:
  • Treatment proved to be safe
  • Improvements in cognition in some participants
  • Improved sleep quality and mood reported
• Study type: Case series / treatment protocol.
• Strengths/Limitations: Valuable real-world research; larger controlled RCTs are needed.

6) Hormonal balance

1. Hamblin MR. Mechanisms of PBM — mitochondrial & NO release affecting endocrine cells (2017)

https://pmc.ncbi.nlm.nih.gov/articles/PMC5523874/

• Population: Mechanistic studies + limited human data.
• Intervention: Red and near-infrared photobiomodulation.
• Key findings:
  • Increase in ATP production
  • Release of nitric oxide (NO)
  • Biological effects that may influence endocrine cell activity and stress response
• Study type: Mechanistic review.
• Strengths/limitations: Strong biological rationale; few direct hormonal clinical RCTs.

2. Yosefov-Abramson / Hernández-Bule 2024 — PBM effects on reproductive tissues

https://pmc.ncbi.nlm.nih.gov/articles/PMC11049838/

• Population: Animal models + small human pilot studies.
• Intervention: Local red/NIR PBM on reproductive tissues.
• Key findings:
  • Improved follicle activity and viability in animal models
  • Improved mitochondrial function
  • Improved blood flow in reproductive structures
• Study type: Preclinical review + pilot human data.
• Strengths/Limitations: Promising, but limited human hormonal data.

3. Liebert A et al. PBM and systemic neuroimmune/endocrine modulation (2020)

https://pmc.ncbi.nlm.nih.gov/articles/PMC7673843/

• Population: Preclinical and clinical studies in various conditions.
• Intervention: Systemic PBM (transcranial and peripheral).
• Key findings:
  • Modulation of inflammatory markers
  • Influence on the hypothalamic–pituitary–adrenal (HPA) axis
  • Possible role in stress regulation and hormonal balance
• Study type: Narrative review.
• Strengths/Limitations: Strong mechanistic support; lack of large human hormonal RCTs.

4. Clinical pilot studies — thyroiditis, thyroid nodules, reproductive medicine (Hernández-Bule 2024)

https://pmc.ncbi.nlm.nih.gov/articles/PMC11049838/

• Population: Small groups of patients with thyroid problems or fertility issues.
• Intervention: Targeted red/NIR PBM on thyroid or pelvic area.
• Key findings:
  • Improved blood circulation
  • Some relief of symptoms
  • Variable changes in hormone levels (not consistent)
• Study type: Pilot clinical observations.
• Strengths/Limitations: Promising but small numbers + inconsistent hormonal outcomes.

5. Laakso EL (2023) — PBM effects on gut–brain–endocrine axes

https://pmc.ncbi.nlm.nih.gov/articles/PMC10216148/

• Population: Mechanistic + small human studies.
• Intervention: Transcranial and peripheral PBM.
• Key findings:
  • Modulation of mitochondria in hormonal and metabolic pathways
  • Influence on gut-brain-hormone communication
  • Possibly relevant for stress, energy and hormonal regulation
• Study type: Review.
• Strengths/limitations: Strong theoretical basis; few large human data studies.

6. Hernández-Bule et al. (2024) — PBM & endocrine function review

https://pmc.ncbi.nlm.nih.gov/articles/PMC11049838/

• Population: Human clinical studies, small RCTs, animal models and mechanistic studies.
• Intervention: PBM on endocrine-related areas (thyroid, brain, testes).
• Key findings:
  • Possible effects on cortisol, testosterone, thyroid hormones and melatonin
  • Mechanistic links via mitochondrial stimulation and neuroendocrine signaling
• Study type: Systematic review.
• Limitations: Few large RCTs; hormonal outcomes often secondary; wide variation between protocols.

7) Better sleep

1. Saltmarche A, et al. Significant improvements in cognition & sleep reported in dementia patients after PBM (2017)

https://pubmed.ncbi.nlm.nih.gov/28186867/

• Population: Persons with mild to moderate dementia.
• Intervention: Repeated photobiomodulation (transcranial/near-infrared).
• Key findings:
  • Improved sleep quality
  • Less nighttime restlessness
  • Improvements in cognitive functions
• Study type: Case series.
• Strengths/Limitations: Consistent caregiver reports, but no control group.

2. Nizamutdinov D, et al. tNIR in dementia: improved sleep & mood (2021)

https://pmc.ncbi.nlm.nih.gov/articles/PMC8219492/

• Population: Dementia patients.
• Intervention: Repeated tNIR treatments at home.
• Key findings:
  • Improved sleep quality within approximately 7 days
  • Improved mood
• Study type: Case series/controlled protocol.
• Strengths/limitations: Real-world setting; not a blinded RCT.

3. Gaggi NL, et al. Enhancing sleep, wakefulness, and cognition with photobiomodulation (2025 review)

https://pmc.ncbi.nlm.nih.gov/articles/PMC12350269/

• Population: Healthy volunteers and clinical groups.
• Intervention: Transcranial PBM, intranasal PBM, and bright-light therapy.
• Key findings:
  • Improved daytime alertness
  • Possible support for nighttime sleep
  • Effects via circadian and mitochondrial pathways
• Study type: Review (2025).
• Strengths/Limitations: Mix of intervention methods; emerging field of research.

4. Urquhart EL, et al. tPBM changes EEG & cognition; sleep-related EEG changes noted (2020)

https://pmc.ncbi.nlm.nih.gov/articles/PMC7587286/

• Population: 20 healthy adults.
• Intervention: One session of 830 nm transcranial PBM.
• Key findings:
  • Increased delta and theta EEG activity (associated with relaxation & sleep pressure)
  • Short-term cognitive improvements
  • EEG profile showed similarities with early sleep cycles
• Study type: Experimental crossover study.
• Strengths/Limitations: Strong neurophysiology, but sleep itself not a primary outcome.

5. Bragato EF et al. (2023) — LED Mask RCT protocol including sleep as outcome

https://pmc.ncbi.nlm.nih.gov/articles/PMC9902007/

• Population: 60 women between 35 and 60 years old.
• Intervention: 633 nm and 830 nm LED mask, 20 minutes per session, 3× per week, for 8 weeks.
• Key findings: This is a protocol study — sleep is measured via PSQI, but no results have yet been published.
• Study type: Randomized, double-blind, placebo-controlled protocol.
• Strengths/Limitations: Strong design; results pending.

6. Hamblin MR (2017) & Laakso EL (2023) — PBM and melatonin/circadian mechanisms

https://pmc.ncbi.nlm.nih.gov/articles/PMC5523874/

• Population: Animal models, cell studies, and indirect human data.
• Intervention: Red (630–660 nm) and near-infrared (800–850 nm) PPE.
• Key findings:
  • Increased cytochrome c oxidase activity
  • Increase in ATP and nitric oxide
  • Possible influence on melatonin synthesis
  • Normalization of circadian rhythms in animals
• Study type: Mechanistic review.
• Strengths/limitations: Strong biological basis; few sleep-focused human RCTs.

8) Hair growth

1. Torres AE, et al. Photobiomodulation for the management of hair loss (2021)

https://pubmed.ncbi.nlm.nih.gov/33377535/

• Population: Overview of multiple RCTs in alopecia.
• Intervention: Red (630–660 nm) and near-infrared LED helmets/caps, 2–3× per week for 12–26 weeks.
• Key findings:
  • Several RCTs show an increase in hair density
  • Improvements in hair growth and hair structure
• Study type: Narrative review + summary of RCTs.
• Strengths/Limitations: Broad coverage; protocol variation remains.

2. Hamblin MR. Photobiomodulation for alopecia (2019 review)

https://pmc.ncbi.nlm.nih.gov/articles/PMC6737896/

• Population: Preclinical and clinical studies.
• Intervention: PPE between 630–830 nm in various devices.
• Key findings:
  • Stimulation of mitochondria in hair follicles
  • Effectiveness in androgenetic alopecia and alopecia areata
  • Potential role in recovery after chemotherapy
• Study type: Review.
• Strengths/limitations: Good mechanistic rationale; older review compared to the most recent RCTs.

3. Lodewijckx J, et al. HAIRLASER trial — PBM to accelerate hair regrowth after chemotherapy (2023)

https://pubmed.ncbi.nlm.nih.gov/37060420/

• Population: Breast cancer patients during or after chemotherapy.
• Intervention: Helmet or locally targeted red/NIR PPE according to protocol.
• Key findings:
  • Accelerated hair growth compared to control
  • Improved quality of life and body image
• Study type: Randomized controlled trial.
• Strengths/Limitations: Valuable in a specific clinical group; moderate sample size.

4. Wang YF, et al. Clinical trial comparing three wavelengths for hair growth (2024)

https://pubmed.ncbi.nlm.nih.gov/40398915/

• Population: 68 adults (18–60 years) with hair loss.
• Intervention: PPE with three wavelengths:
  • 650 nm
  • 1550 nm
  • 14,000 nm
  compared to control, for 3 months plus 9 months follow-up.
• Key findings:
  • Increase in hair density in all PBM groups
  • Decreasing density in the control group
  • Reduced sebum production of the scalp
• Study type: Controlled clinical trial.
• Strengths/Limitations: Unique wavelength comparison; medium sample size.

5. Charoensuksira S, et al. Light-guiding microneedle patch + LED helmet (2024)

https://pubmed.ncbi.nlm.nih.gov/39325239/

• Population: 16 patients with androgenetic alopecia.
• Intervention: Microneedle patch combined with LED helmet (522 nm + 633 nm), 50 mW/cm², 40 J/cm², weekly for 24 weeks.
• Key findings:
  • Increased hair density in the treated area
  • Improved hair quality compared to control
• Study type: Small randomized split-area trial.
• Strengths/Limitations: Innovative method; very small sample size.

6. Yang K, et al. Hair growth promoting effects of 650 nm red light (ex vivo)

https://pmc.ncbi.nlm.nih.gov/articles/PMC8577899/

• Population: Ex vivo human hair follicle cultures.
• Intervention: Exposure to 650 nm red light.
• Key findings:
  • Stimulation of follicular activity
  • Upregulation of mitochondrial and growth factor signaling
• Study type: Mechanistic ex vivo study.
• Strengths/Limitations: Strong biological support; no direct clinical application.

9) Improved metabolism

1. Scontri CMCB, et al. Dose-response PBM reduces glycemia in T2DM (2023)

https://pubmed.ncbi.nlm.nih.gov/37171054/

• Population: Individuals with type 2 diabetes in a randomized double-blind crossover design.
• Intervention: Red/near-infrared PPE with time and dose variations.
• Key findings:
  • Drop in blood glucose levels
  • Improvement in heart rate variability (HRV), indicating better autonomic balance
• Study type: Randomized crossover RCT.
• Strengths/limitations: Promising results; larger studies needed.

2. Elnaggar RK, et al. PBMT vs RF vs control in adolescents with obesity (2020)

https://pubmed.ncbi.nlm.nih.gov/32141112/

• Population: Adolescents with obesity.
• Intervention: 635 nm PBM on abdominal fat regions, compared with radiofrequency and control.
• Key findings:
  • Reduction in waist-to-hip ratio
  • Reduction of subcutaneous abdominal fat thickness
• Study type: RCT.
• Strengths/Limitations: Physical measurements improved; short follow-up period.

3. Roche GC, et al. LLLT for reducing hip/waist/abdomen circumference (2017)

https://pubmed.ncbi.nlm.nih.gov/27935737/

• Population: Adults with BMI between 30–40.
• Intervention: 635–680 nm LLLT with multiple treatment sessions.
• Key findings:
  • Significant reduction in waist size
  • Decrease in hip and waist circumference
• Study type: Controlled clinical trial.
• Strengths/limitations: Valid reductions in body size; metabolic biomarkers not the main focus.

4. Magalhães FC, et al. PBM in insulin resistance & metabolic outcomes (2022 review)

https://pubmed.ncbi.nlm.nih.gov/36040371/

• Population: In vitro, animal and human studies.
• Intervention: PPE with various parameters.
• Key findings:
  • Improved mitochondrial function
  • Reduced inflammatory activity
  • Enhanced metabolic signaling in adipocytes and muscle
• Study type: Narrative/systematic review.
• Strengths/limitations: Strong theoretical support; more RCTs in humans needed.

5. Modena DAO, et al. LED PPE on adipose tissue — split-abdomen trial (2023)

https://pubmed.ncbi.nlm.nih.gov/37851070/

• Population: Obese women.
• Intervention: Red and infrared LED PBM focused on separate parts of the abdomen.
• Key findings:
  • Stimulation of mitochondrial activity in fat cells
  • Local reduction of adipose tissue
• Study type: Non-randomized split-area study.
• Strengths/limitations: Interesting mechanistic markers; lack of randomization.

6. Liu S, et al. tPBM improves metabolic parameters in diabetic mice (Nature Communications, 2023)

https://www.nature.com/articles/s42003-023-05630-3

• Population: Diabetic mouse models.
• Intervention: Transcranial PBM.
• Key findings:
  • Improved effectiveness of insulin therapy
  • Altered microglial activity (inflammation modulation)
  • Increase in energy consumption and exercise
• Study type: Preclinical animal research.
• Strengths/Limitations: Strong mechanistic evidence; clinical translation needs confirmation.

10) Better mood / less anxiety or depression

1. Cassano P., et al. Transcranial photobiomodulation for major depressive disorder — pilot RCT (2018)

https://pmc.ncbi.nlm.nih.gov/articles/PMC7864111/

• Population: Adults with major depressive disorder (MDD).
• Intervention: Transcranial near-infrared PBM targeted to the prefrontal cortex.
• Key findings:
  • Observable antidepressant effects
  • Improved mood compared to baseline
  • Good tolerance and feasibility
• Study type: Randomized, double-blind, sham-controlled pilot study.
• Strengths/Limitations: Strong design but small sample size.

2. Ji Q., ​​et al. Photobiomodulation improves depression symptoms — meta-analysis (2024)

https://pubmed.ncbi.nlm.nih.gov/38356614/

• Population: RCTs and controlled trials in individuals with depressive complaints.
• Intervention: Transcranial and peripheral PBM.
• Key findings:
  • Significant reduction in depressive symptoms compared to placebo
  • Limited number of high-quality RCTs available
• Study type: Systematic review and meta-analysis.
• Strengths/limitations: Statistically proven effect; heterogeneous protocols.

3. Cho Y., et al. Meta-analysis: Efficacy of tPBM for depressive symptoms (2023)

https://pubmed.ncbi.nlm.nih.gov/37651208/

• Population: Randomized and sham-controlled trials.
• Intervention: Various transcranial PBM protocols.
• Key findings:
  • Support for effectiveness of tPBM
  • Many studies underpowered by small samples
• Study type: Meta-analysis.
• Strengths/Limitations: Thorough analysis, but limited by small trial sizes.

4. Iosifescu DV, et al. ELATED-3 multicenter randomized sham-controlled trial (2022)

https://pubmed.ncbi.nlm.nih.gov/35950904/

• Population: Patients with major depressive disorder across multiple research centers.
• Intervention: Transcranial PBM with predefined irradiance and energy thresholds.
• Key findings:
  • Minimum dose required to achieve clinical effect
  • Low doses showed no effect
• Study type: Multicenter randomized controlled trial.
• Strengths/limitations: Emphasizes the importance of correct dosing; variation between centers.

5. Guu TW, et al. Wearable tPBM for MDD — randomized double-blind sham-controlled trial (2025)

https://pubmed.ncbi.nlm.nih.gov/39706483/

• Population: Persons with major depressive disorder.
• Intervention: Self-administered portable tPBM equipment.
• Key findings:
  • Well tolerated and feasible in daily use
  • Low dose proved insufficient for antidepressant effect
  • Improved sleep quality was reported
• Study type: Randomized double-blind sham-controlled study.
• Strengths/limitations: Realistic practical situation; low dosage limits effectiveness.

6. Coelho DRA, et al. Dose-finding RCT of tPBM — neurometabolite changes & clinical correlations (2025)

https://pubmed.ncbi.nlm.nih.gov/40429396/

• Population: Adults with MDD.
• Intervention: Varying doses of transcranial PBM.
• Key findings:
  • Dose-dependent changes in neurometabolites (NAA, Cho, Cr)
  • Correlation between metabolic changes and clinical improvement
• Study type: Randomized double-blind dose comparison study.
• Strengths/Limitations: Strong mechanistic design; early-phase studies.

11) Reduction of inflammation (arthritis & autoimmune diseases)

1. Zhang R., et al. Mechanisms & efficacy of PBM in inflammatory disease (2023)

https://pmc.ncbi.nlm.nih.gov/articles/PMC10531845/

• Population: Human and animal studies focused on inflammatory diseases.
• Intervention: Various red and near-infrared PPE protocols.
• Key findings:
  • Decrease in inflammation markers
  • Improved tissue repair mechanisms
  • Positive effects in joint diseases and autoimmune models
• Study type: Systematic review (2023).
• Strengths/Limitations: Very comprehensive; variation in treatment protocols remains a limitation.

2. Hamblin MR. Anti-inflammatory effects of PBM — mechanistic review (2017)

https://pmc.ncbi.nlm.nih.gov/articles/PMC5523874/

• Population: Cell, animal and human studies.
• Intervention: Red and near-infrared light.
• Key findings:
  • Decrease in oxidative stress
  • Decrease in pro-inflammatory cytokines
  • Increased vasodilatory nitric oxide (NO)
  • Modulation of mitochondria and immune activity
• Study type: Mechanistic review.
• Strengths/Limitations: Strong biological foundation; clinical PBM protocols vary widely.

3. Oliveira S., et al. PBM for knee osteoarthritis — systematic review (2024)

https://pubmed.ncbi.nlm.nih.gov/38775202/

• Population: RCTs in patients with knee osteoarthritis.
• Intervention: Laser or LED PPE with different parameters.
• Key findings:
  • Pain reduction
  • Possible improvement in mobility and functioning
• Study type: Systematic review and meta-analysis (2024).
• Strengths/Limitations: Aggregated data; low certainty due to heterogeneous protocols.

4. González-Muñoz A., et al. PBM for chronic pain & inflammation — systematic review (2023)

https://pmc.ncbi.nlm.nih.gov/articles/PMC10094541/

• Population: Persons with chronic pain and inflammatory conditions.
• Intervention: Laser- and LED-based PPE.
• Key findings:
  • PBM shows beneficial effects on pain and inflammation
  • Different indications benefit to varying degrees
• Study type: Systematic review.
• Strengths/limitations: Comprehensive overview; need for standardized RCTs.

5. Stausholm MB., et al. Efficacy of LLLT in knee osteoarthritis — BMJ Open (2019)

https://pmc.ncbi.nlm.nih.gov/articles/PMC12326686/

• Population: Placebo-controlled LLLT trials in knee osteoarthritis.
• Intervention: Various dosing protocols for LLLT.
• Key findings:
  • Significant reduction in pain
  • Improved joint function
• Study type: Systematic review and meta-analysis (2019).
• Strengths/Limitations: Strong evidence, but variation in dosages between studies limits comparability.

6. Lourinho I., et al. LLLT in adults with rheumatoid arthritis — systematic review & meta-analysis (2023)

https://pmc.ncbi.nlm.nih.gov/articles/PMC12326686/

• Population: Adults with rheumatoid arthritis.
• Intervention: Various LLLT/PBM protocols.
• Key findings:
  • Decrease in inflammation markers
  • Pain reduction
  • Improvements in functioning (in some studies)
• Study type: Systematic review and meta-analysis (2023).
• Strengths/Limitations: Promising, but small cohorts and varying methodology.